Iris cover implant

ABSTRACT

The invention concerns an iris cover implant intended to cover at least partially the iris of an eye, the cover implant comprising a body having a first face that is an opaque face and, on an opposite second face, at least one attachment member that extends outwardly from the body and is fixed thereto, the at least one attachment member comprising at least two clamping portions that are able to attach the body to an iris of an eye by clamping.

The invention concerns inter alia an iris cover implant.

The young human eye can naturally focus from far to near objects. Themechanism underlying this focus is called the accommodation process. Itis composed of three main aspects: first, a convergence of the eye ballas objects get closer, then—for a given luminosity—an increase in thepupil constriction, and finally an adjustment of the crystalline lensshape modulated by the ciliary muscle contraction.

As the eye naturally ages, it becomes harder and harder for it to adjustto near objects. While aging, the subject loses progressively its nearvision and is able to create a sharp picture only for far objects. Thisnatural vision affect is called presbyopia. It is assessed that by 2020,around two billion people will have to deal with this optical affect.Presbyopia is experienced as a blurring of the person's vision andfrequently arises when the person is reading a document or working at acomputer. An untreated patient may compensate by moving the viewedmaterial farther away than would be their previous practice. Roots ofpresbyopia lays in the aging of the crystalline lens that becomes largerand stiffer, and therefore harder to deform whereas convergence andpupil constriction seem not to be affected.

Many attempts have been done to correct presbyopia. The most common andlegacy solution is the use of a pair of reading glasses: as far visionis preserved, the subject can wear glasses to be able to read a book forinstance. While this solution is not invasive at all, wearing glassescan be seen as neither aesthetic nor practical for the patient, ashe/she needs to put them on and off depending on the distance of theobject he is looking at. To solve these problems, multifocal andprogressive glasses have been developed. They offer, at least, a firstrefractive correction for distance viewing and a second refractivecorrection for viewing near objects; sometimes multiple distance visionby progressive curvature changes.

Surgical attempts have been performed to correct permanently in a moreinvasive manner the symptoms of presbyopia and restore an amplitude ofvision without the need of glasses, often considered as an aging symbol.A common treatment is to induce a static adjustment of the refractivepower of one eye of the person. In this way the other eye is used forfar vision, and the brain processes the two signals of both eyes tocreate a new depth of vision that is suitable for near and far images(monovision).

There are different ways to correct an eye for near vision. Changes canbe performed on the cornea, by reshaping the latter with laser forinstance, or placing a refractive implant inside the corneal tissues(Corneal Inlays). The other solution is to replace the crystalline lenswith an implant, adapted to a set of specific distances of vision, namedMultifocal Intra Ocular Lens (or MIOLs). This type of device comprisesdifferent corrections for a least two specific distances. However thistype of treatment suffers drawbacks: it induces a loss of luminosity,halos, glares and flares in night vision for instance.

Original attempts that have been done to try to restore the amplitude ofvision may also be noticed such as scleral implants which, for instance,focus on a release of the zonular tension without getting the expectedperformances.

However, none of the above solutions has proved to be satisfactory.

Taking account of the above, the inventors have searched for a neweffective implant to compensate presbyopia.

When searching for such a new implant the inventors have conceived a newimplant configuration and have discovered other applications for thisnew implant configuration.

According to an aspect of the invention, a new iris implantconfiguration is an iris cover implant that is intended to cover atleast partially the iris of an eye, the cover implant comprising a bodyhaving a first face that is an opaque face and, on an opposite secondface, at least one attachment member that extends outwardly from thebody and is fixed thereto, the at least one attachment member comprisingat least two clamping portions that are able to attach the body to aniris of an eye by clamping.

The iris cover implant is adapted to be located on an iris of a humaneye and attached thereto.

The attachment member or each attachment member is fixed or connected tothe cover implant body which means that the attachment member(s) is(are)not a tool which serves only for the placement and attachment of theimplant on an iris and which is removed afterwards. In contrast, theattachment member(s) remains in situ in a clamped engagement with aniris portion during the whole duration of the use of the implant in theeye. In other words, the attachment member(s) remains attached in apermanent manner to the anterior face of the iris during the use of theimplant contrary to a tool. Thus, the use of such attachment member(s)does not mean that no external tool can be used for helping thepositioning of the cover implant on the iris.

The clamping portions of the attachment member or each attachment membermay carry out a clamping function on the iris, i.e. on a portion of theanterior surface of the iris, in particular a ridge thereof (naturaliris fold) to clamp an iris portion or ridge between the two facingportions. Securing the cover implant body to the iris is thereforepossible without piercing or traversing the iris tissue. This makes itpossible to remove the cover implant body without strongly damaging thetissue with holes.

The two clamping portions are close to each other in their initialposition (clamping position) so as to be able to clamp an iris ridgebetween the two facing portions. The two clamping portions may belocated at a distance from each other that is less than 3 mm, preferablyless than or equal to 2 mm, e.g. less than or equal to 2 mm. If thedistance between the two facing portions of the attachment member oreach attachment is greater clamping an iris ridge will not be possibleor will prove to be very difficult.

To be noted that the clamping portions may have each at their free end(opposite the end that is connected to the second face) an enlarged partor head with a shape that is appropriate to firmly and safely clamp aniris ridge, e.g. with a flat surface facing the flat surface of theother clamping portion.

The iris has a shape of a disc or annulus and the iris cover implant isintended to cover at least a portion of the iris whatever the shape ofthe implant. Generally speaking, the implant may be located on a radiusof the iris and oriented towards the center of the iris.

The iris cover implant may have different shapes, such as an overallshape of a segment, an angular sector or area in some instances etc.

Generally speaking, the iris cover implant body has two opposite faces:a first face is opaque to light and a second one is provided with theattachment member that is intended to cooperate with the iris of the eye(more particularly, the anterior surface of the iris) so as, for theiris cover implant, to be attached to the iris (two functional zones ofthe body). The opaque face is then intended to be visible through thecornea of the eye. The first and second faces are defined as opposite inthat they are faces of the body that are both oriented in oppositedirections, one being intended to face the cornea when the implant isattached on the iris, while the other is intended to face the surface ofthe iris. Both faces may not strictly extend one above the other. Oneface may even extend further than the other so that the extended portionof this face does not overlap the other one.

Such an iris cover implant is efficient and easy to install on the iris(pupillary margin) due to the at least one attachment member.

In addition, it is not intended to be in contact with the iridocornealangle, which avoids ocular hypertension and following severcomplications. It is neither intended to be in contact with theendothelium of the cornea to avoid endothelial failure and followingsevere complications.

With such a cover implant, more or less severe complications of iris canbe avoided: infections, anterior uveitis, ocular hypertension, glaucoma,endothelial failure, corneal oedema and decompensation.

Example of complication secondary to cosmetic artificial iris anteriorchamber implants can be found in a case report from Yusrah Shweikh,Sally Ameen and Ali Mearza, BMC Ophthalmology, 201515:97.

The cover implant is intended to be placed into the anterior chamber ofthe eye, that is, within aqueous humor.

No biocompatibility issue will arise on a long term basis with this newimplant configuration. No inflammatory reaction will take place afterthe installation of such a cover implant.

More generally, such a cover implant may be used for the opticalenhancement of an eye, including the compensation of presbyopia, regularametropia or regular astigmatism.

More particularly, such a cover implant may be used for presbyopiacorrection or compensation by forming, generally together with othercover implants simultaneously, a diaphragm that is intended to reducethe diameter of the aperture of a constricted iris.

Such a cover implant may alternatively be used for visual or cosmeticenhancement, alteration or repair of the iris anterior surface (visiblethrough the cornea as the “color of the eye”).

In such applications a cover implant may be used alone or in combinationwith other cover implants, e.g. to hide an iris deformity or to locallyor wholly modify the color.

In these applications, the iris cover implant or implants are attachedon the iris in a position such that the opaque face is above the iris.Here the cover function does not require for the opaque face to extendbeyond the iris inner edge.

When searching for a way to compensate presbyopia, the inventors havenoted that it could be interesting to reduce the aperture of the eye(pupil) so as to increase the depth of field. In particular, they havenoted that the ability of the lens to change its shape decreases withtime, but the pupil constriction keeps working. The inventors have alsonoted that elderly persons who can no longer accommodate with theircrystalline lens exacerbate the phenomenon of pupil constriction.Similarly, to the way a photographer increases the depth of field of itscamera, pupil constriction leads to a reduction in the diameter of thepupil, thereby suppressing marginal rays. The paraxial rays that remainand pass through the fully constricted pupil are thus able to create asharp picture on the retina for a wider range of distances of vision.The suppression of these marginal rays using a small aperture is calledstenopeic effect or “pinhole effect”. However, the inventors haverealized that, even though the phenomenon of pupil constriction isexacerbated with elderly persons, this is not sufficient to compensatefor the other effects of the eye aging, including presbyopia.

From these statements the inventors have thought of further reducing thediameter of a constricted iris (enhancement of natural pupilconstriction) through the use of several iris cover implants, e.g. ofthe above-mentioned type, to correct presbyopia.

When installed on an iris the plurality of cover implants are arrangedin a radial distribution around the central aperture of the iris (pupil)and attached to the iris. The plurality of cover implants may radiallyconverge towards the center of the central aperture.

Each cover implant may be attached on the anterior surface of the irisin a position such that at least one zone of its opaque face that has anoptical function forms a cantilevered portion with respect to the inneredge of the iris that bounds outwardly the pupil. Therefore, the opaqueoptical face extends in the central aperture (the pupil) beyond the irisinner edge when viewed through the cornea. The cantilevered portion withthe opaque optical zone may be viewed as a diaphragm portion.

The cover implants may be arranged on the iris so that when pupil isdilated (for far vision and/or in dark conditions) the cover implantsare away from each other.

When pupil is constricted (this phenomenon of constriction takes placefor near vision and/or under daylight conditions) the cover implants arelocated one close to another so as to form all together a diaphragm andfurther reduce the diameter of the natural reduced central aperture ofthe iris.

By further reducing the aperture of the naturally constricted iris,suppression of the marginal rays can be obtained and the depth of fieldcan be increased (pinhole effect) without significantly and permanentlyreducing the light adaptation ability of the implanted eye (e.g.luminosity in far vision must be preserved).

Such a diaphragm configuration makes it possible to create a stenopeiceffect which efficiently improves near vision.

This pinhole effect is obtained only when needed, i.e. the effect is nonpermanent whatever the position of the pupil while the cover implantsare always present on the iris and move with the latter. When pupil isdilated, the cover implants are away from each other and, therefore, donot lead to a pinhole effect. This effect may be more or lessprogressive when pupil is constricting. The implant may therefore beconsidered as dynamic since its position in the eye changes with theiris movement and its technical effect is produced dynamically, i.e.during the constriction movement of the iris.

Thanks to this new iris implant configuration the amount of light is notsignificantly reduced for distance vision or low light conditions(mesopic) vision. This implant makes it possible to adapt the conditionsof luminosity and focus. This implant is adapted to the patient's eyespecificities and adapts dynamically so that the vision in night or darkconditions is not limited while a pinhole diameter could be perfectlyfitted (customized to the eye).

To be noted that the part of the body that carries out an opticalfunction is not necessarily a detachable or removable part of the bodybut may be integrated in the cover implant.

According to other possible features:

the opaque face extends at least in a plane that is substantiallyperpendicular to the direction of extension of the at least oneattachment member relative to the second face of the body;

the at least two portions are able to move away from each other underthe action of an external force in a plane containing the direction ofextension of the at least one attachment member relative to the secondface of the body (this direction of extension is generally perpendicularto the second face of the body, and possibly to the first face if bothfaces are parallel), the body being able to elastically bend within theplane when submitted to an external force so as to cause said at leasttwo portions to move away from each other from an initial position, saidat least two portions being able to return to their initial position (aclamping position) in the absence of any external force (this elasticbending movement can me made a repeated number of times without causingany damage to the implant); the two facing portions are spaced apartfrom each other in their initial position by a distance that allows toclamp an iris ridge therebetween and can be moved away from each otherin a direction that tends to increase the initial distance therebetween;this direction can be a combination of an axial direction (perpendicularto the two facing portions) and the direction of outward extension ofthe attachment member; in the bent position, the two portions are spacedapart from each other by a distance that enables placement of theportions on either side of an iris edge; to be noted that the bendingmovement is made possible due to the inherent properties of the wholebody material (the whole body deforms during this bending, not only onezone of the body even though some part of the body may be conceived forfacilitating bending of the body; bending of the body is generally notpossible beyond a given angular range, e.g. 90°; generally speaking, thebody cannot be bent so that the two extreme bent parts thereof come intocontact with each other (as in folding movement of a paper sheet)), i.e.this is not a folding movement; the bending movement is made about alongitudinal direction (perpendicular to the above plane) and thebending force may be applied on two opposite peripheral edges of thebody that are spaced apart from each other along a transverse direction(these two edges run parallel to the longitudinal direction);attachment/securing of the body to one or more portions of the irisanterior surface is therefore quite simple since this is not necessaryto cause complex deformation to the body in different directions toachieve attachment

the body has at least two receiving portions that are each adapted toreceive an instrument or a portion of an instrument for elasticallybending the body; each receiving portion may take the shape of a groovethat opens out towards the exterior of the body, i.e. in a directionaway from the body;

the at least one attachment member is integral with the body; thissimplifies the conception of the cover implant compared to an attachmentmember which is fixed to the cover implant body afterwards, e.g. in aremovable manner;

the at least two attachment members are spaced apart from each otheralong a first direction that is substantially perpendicular to thedirection of extension of the at least one attachment member, the bodyhaving a thickness along the direction of extension of the at least oneattachment member relative to the second face of the body, the thicknessof the body being reduced in a zone of the body that is located betweenthe two zones where the at least two attachment members are disposed;

the body comprises a frame provided with the at least one attachmentmember and a cover member assembled with the frame, the cover memberincluding the opaque face; the two-part body may be easily manufactured;such a configuration makes it possible to customize the cover member,e.g. by selecting appropriate materials, pigmentation or the like,whereas the frame may be common to all the cover implants (ex: one frameper cover member); when the cover member is entirely opaque it masks theat least one attachment member from the above (according to a view takenthrough the cornea, facing the iris); when assembled the cover memberextends above the frame and covers at least a portion thereof, inparticular at least the portion where the attachment member(s) is(are)located; the frame may extend perpendicularly to the direction ofextension of the attachment member(s) in two planar directions; thecover member (e.g. it may be curved as a tile) may also extend in thesame two planar directions and has a longitudinal extension that covers(overlaps or is over) the whole longitudinal extension of the frame orat least the portion where the attachment member(s) is(are) located;

the frame and the cover member are mechanically engaged with each other;the cover member may be engaged inside the frame or vice versa; thecover may be inserted in a slot defined in the frame;

the frame has two receiving portions that are each adapted to receivethe cover member; such receiving portions may be inwardly orientedrelative to the frame and, e.g. may be facing each other; such receivingportions may take the shape of rails or grooves; the two receivingportions may be located on, or close to, two opposite edges of the framethat are spaced apart from each other along a transverse direction(these edges run parallel to the longitudinal direction of the body whenit has a longitudinal extension);

the frame comprises two parallel spaced apart beams with two attachmentmembers located on the two beams respectively; the two parallel beamsmay be perpendicular to the longitudinal direction of the body andperpendicular to the above two opposite edges of the frame (when thecurrent feature is combined with the previous feature);

the cover member also includes a mechanical portion that is assembledwith the frame;

the mechanical portion is opaque, transparent or pigmented in a way toobtain a specific visual appearance;

the cover member and the frame are each able to be elastically deformed;this may make it possible to easily mount the cover member to the frame;the cover member may take the shape of a flexible foil or tile;

the at least one attachment member is a clamping member; a clampingmember makes it possible to clamp a portion of the anterior surface ofthe iris; several clamping members may be used;

the body comprises a frame provided with the at least one attachmentmember and a cover member including the opaque face, the frame and thecover member being made of a single piece; when the cover member isentirely opaque it masks the at least one attachment member from theabove (according to a view taken through the cornea, facing the iris);

the opaque face has at least one zone that is an opaque optical face;this feature corresponds to an iris cover implant that is, inter alia, adiaphragm implant and has an optical function when implanted on the irisof an eye;

the opaque optical face belongs to an optical portion that extendsbeyond the frame (in a longitudinal direction); here the optical portionis intended to be located above the pupil margin (beyond the iris inneredge) so as to reduce the diameter of the latter when the cover implantis attached to the iris; to be noted that the entire opaque face of thecover member extends both above the frame and beyond the latter, onlythe zone extending beyond the frame having an optical function(diaphragm); in another embodiment, the opaque optical face constitutesthe only opaque zone of the cover member; the optical portion maylongitudinally or axially extend the mechanical portion;

the opaque optical portion and the mechanical portion may form togethera single piece, which proves to be easy to manufacture.

Another aspect of the invention concerns an iris cover implant intendedto cover at least partially the iris of an eye, the cover implantcomprising a body having a first face that is an opaque face and, on anopposite second face, at least one attachment member that extendsoutwardly from the body, the at least one attachment member being ableto attach the body to an iris of an eye so as to move together with thenatural movement of the iris. Such an iris cover implant (diaphragmimplant) is thus a dynamic implant (or part of a whole implant) that iscontrolled by the movement of the iris. Such an iris cover implant mayhave an optical correction function and protrudes inside the centralaperture of the iris to carry out optical correction. The protrusion mayintervene only when optical correction is necessary, i.e. when the pupilis in a constricted position, for example to reduce the pupil size. Theiris cover implant may therefore act as a dynamic diaphragm togetherwith the natural movement of the pupil. Any of the explanation andfeatures given in relation to the above first aspect of the inventionmay also be applied here.

The invention also concerns a surgical kit comprising a plurality ofcover implants (e.g. two or more than two or three) as defined above inany of the two aspects (with the main features of the aspect or alsowith at least some of the possible other features). These cover implantsare then placed inside the eye, e.g. through a corneal incision, andnext attached to the anterior surface of the iris by means of aspecifically designed surgical instrument such as an appropriatesurgical forceps thanks to the above-described attachment members. Theplurality of cover implants forms a multi-component iris (intraocular)implant acting as a diaphragm when attached to an iris of an eye(presbyopia treatment). The plurality of cover implants provide alltogether a stenopeic effect as described above when all attached to theiris and the iris is constricted enough. The multi-component irisimplant is a dynamic implant that is controlled by the natural movementof the iris.

The invention also concerns a surgical kit comprising a plurality ofcover implants (e.g. two or more than two or three) as defined above inany of the two aspects (with the main features of the aspect or alsowith at least some of the possible other features), the plurality ofcover implants forming a multi-component iris (intraocular) implantacting as a partial or total artificial iris when attached to an iris ofan eye thanks to the above-described attachment members. Here the coverimplants are intended to replace at least in part the visual aspect ofthe anterior surface on an iris. In practice, the cover implants areintended to at least partially cover the natural iris. This makes itpossible to replicate, alter or enhance the cosmetic/visual appearanceof the natural iris surface. The multi-component iris implant is adynamic implant that is controlled by the natural movement of the iris.

The invention also concerns an assembly of several cover implants (e.g.two or more than two or three) as defined above in any of the twoaspects (with the main features of the aspect or also with at least someof the possible other features), the plurality of cover implants forminga single iris (intraocular) implant acting as a diaphragm when attachedto an iris of an eye thanks to the above-described attachment members.This assembly is intended to be put in place as a whole on the iris. Themulti-component iris implant is a dynamic implant that is controlled bythe natural movement of the iris.

The invention also concerns an assembly of several cover implants (e.g.two or more than two or three) as defined above in any of the twoaspects (with the main features of the aspect or also with at least someof the possible other features), the plurality of cover implants forminga single iris (intraocular) implant acting as a partial or totalartificial iris when attached to an iris of an eye thanks to theabove-described attachment members. This assembly is intended to be putin place as a whole on the iris. The multi-component iris implant is adynamic implant that is controlled by the natural movement of the iris.

The detailed aspects which will be described with reference to thedrawings may complete the above-mentioned more general aspects andtherefore may be combined with them. To be noted that theabove-mentioned more general aspects may be applied to other embodimentsthan those described thereafter.

Other features and advantages will emerge in the course of the remainderdescription, given by way of non-limiting example only, with referenceto the following drawings, in which:

FIGS. 1 to 3 illustrate a frame of a cover implant according to anembodiment of the invention;

FIGS. 4A-C illustrate a cover member of a cover implant according to anembodiment of the invention;

FIGS. 5A-C illustrate the principle of the attachment of a cover implanton the iris;

FIGS. 6A-C illustrate the assembling operations of the frame of FIGS.1-3 with the cover member of FIGS. 4A-C;

FIG. 7 is a view of a variant embodiment of an attachment member;

FIG. 8A-C illustrate a Monobloc cover implant according to anotherembodiment of the invention;

FIGS. 9A-C illustrate different possible variant embodiments of anattachment member;

FIGS. 10A-E illustrate different possible configurations for the opaqueoptical portion of a cover implant;

FIGS. 11A-C are different successive views showing the pupilconstriction and the associated arrangement of cover implants attachedto the iris for the cover implant of FIG. 10A;

FIGS. 12A-C are different successive views showing the pupilconstriction and the associated arrangement of cover implants attachedto the iris for the cover implant of FIGS. 10D-E;

FIGS. 13A-D are views showing different possible configurations for theopaque optical of several cover implants attached to the iris;

FIGS. 14A-D illustrate the main steps of a possible surgical method forimplanting a cover implant on an iris;

FIG. 15 represents a cover implant with no optical function according toan embodiment of the invention;

FIG. 16A-D illustrate different views of another cover implant with bothoptical and covering functions according to an embodiment of theinvention;

FIG. 17 represents the cover implant of FIGS. 16A-D positioned on aniris;

FIG. 18 represents another cover implant with no optical functionpositioned on an iris according to an embodiment of the invention;

FIGS. 19A-C schematically illustrate the installation constraints for acover implant according to an embodiment of the invention.

In a first embodiment an iris (intraocular) cover implant carries out acover or overlap function relative to the iris on which it is intendedto be fixed.

The terms “cover implant” will be used in the remainder of thedescription whatever the embodiments and the function/application of theimplant since the iris will always be covered by at least a portion orcomponent of the implant.

Here the cover implant is made in two parts as illustrated in FIGS. 1 to7. The cover implant is made in a biocompatible material or combinationor mixture of biocompatible materials. By way of example, the coverimplant is made of silicon or hydrophilic acrylics or hydrophobicacrylic or elastomer and, for example, may be cross-linkedpolydimethylsiloxanes possibly reinforced with silica or EMA (ethylmethacrylate), or HEMA (Hydroxyethyl methacrylate), or a combination ofboth previous examples (co-polymers) (material adapted for a medicaluse).

As illustrated in FIGS. 1 to 3, the cover implant 10 (cover implant 10is represented in FIG. 6C only once assembled) comprises a body thatcomprises a frame 12 provided with at least one attachment member.

The frame is made of a material or a combination of materials that allowelastic deformation of the frame. PMMA may be an example of appropriatematerial (transparent or died in the mass).

In the present embodiment there are two attachment members 14, 16 thatare disposed on one and the same side or face of the frame that is hereoriented downwards. The attachment members are here made integral withthe cover implant body, in particular the frame. In a variant embodimenta single attachment member or more than two can be envisaged.

The frame 12 has an overall axial or longitudinal extension along alongitudinal axis X and transverse extension along a transverse axis Y.The frame 12 also extends perpendicularly to the plane X, Y along axis Zthat defines its thickness (FIG. 2).

The attachment members 14, 16 extend outwardly from the frame 12 alongan overall direction (axis Z) that is substantially perpendicular to theplane XY.

The frame 12 comprises here two transverse beams 18, 20 that are axiallyspaced apart from each other along axis X so as to leave there between acentral opening 22. Cross beams 18, 20 extend along transverse axis Y(fig.1).

The two transverse beams 18, 20 are connected at each of their twoopposite ends to two parallel longitudinal or axial supporting members24, 26. In another embodiment, more than two transverse beams may beenvisaged or a single beam connecting the two supporting members. Thesingle beam may have a longitudinal axis (X) that has not necessarilythe same extension as the supporting members.

For instance, the frame is made of a single piece and may bemanufactured by an injection molded process or standard machining.

The following description will be made for cross beam 18 for the sake ofsimplicity and is identical for beam 20.

When viewed in a front or top view (FIG. 1), each transverse beam has arather narrow central portion (ex 18 a for beam 18) which enlargestowards the two opposite ends 18 b, 18 c where it connects with thesupporting members 24, 26 respectively. Each beam has a curved outlinein FIG. 1 on its two opposite transverse sides (these sides extendtransversely relative to the longitudinal axis X). However, other frontor top view shapes may be envisaged for the beam.

When viewed in a transverse cross section (AA cross section of FIG. 2),each transverse beam has a rather flat and thin shape in a main portion18 d taken along a direction parallel to axis Z. The main portion 18 dincludes central portion 18 a and a lateral extension on either partthereof. Overall the main portion 18 d may extend over a dimension thatsubstantially corresponds here to ⅔ of the length of the beam. However,other ratios may be envisaged. Beyond the main portion 18 d the beamcomprises enlarged lateral portions 18 e and 18 f which have an increasein their thickness (taken along axis Z), e.g. a progressive increase.This thickness increase ensures solid mechanical connection with thesupporting members 24, 26. Furthermore this thickness increase minimizesdeformation, e.g. bending, in the zone of the lateral extensions of thebeams. Put it another way, the thickness reduction in the main portionfavors deformation, e.g. bending, of the beam, which will contribute toopening of the attachment members.

The thinned configuration of the cross beams in their central and mainportions as described above makes it possible to elastically deform theframe in the plane of FIG. 2, e.g. by bending as indicated by the twoarrows.

In the present embodiment, the two attachment members 14, 16 are locatedon the underside of the beams 18, 20 respectively in the central portion18 a, 20 a thereof.

Each attachment member may be a clamping member and may comprise atleast two clamping portions or jaws 14 a, 14 b and 16 a, 16 b.

In the present embodiment, the two jaws are spaced apart from each otherin their stable, non-deformed initial position as represented in FIGS. 1to 3. Depending on the object to be clamped between the two jaws the gapthere between may be more or less wide. Generally speaking, the gap ordistance along transverse axis Y is less than or equal to 3 mm.

FIG. 5A illustrates very schematically the initial position of theclamping jaws 14 a, 14 b of cover implant 10. In FIGS. 5A-C coverimplant 10 is wholly assembled as in FIG. 6C that will be subsequentlydescribed. The attachment principle illustrated in FIGS. 5A-C alsoapplies to a monobloc cover implant.

When an external bending force is exerted on the two supporting members,here along axis Y, the frame 12 bends in the plane of FIG. 5A (this isalso the plane of FIG. 2 as indicated by the arrows) and the two jaws ofeach clamping member move away from each other, in particular alongtransverse axis Y, so as to enlarge the gap (FIG. 5B).The cover implantis caused to be moved toward the anterior surface of the iris (alongaxis Z) and the jaws come close to this surface so as to be positionedon either part of an iris ridge.

When the bending force does no longer exert, the frame returns to itsinitial position of FIG. 5A and the jaws may clamp an iris ridge P(natural iris fold) there between (FIG. 5C).

The axial supporting members 24, 26 (FIGS. 1-3) have each a transverseprofile or cross section that may be identical along the whole length ormay present locally some controlled irregularities on purpose. Suchcontrolled irregularities may serve as axial stops for a second part ofthe cover implant body (cover member) when the latter is axially engagedinto the frame.

In the present embodiment the axial supporting members 24, 26 mayperform a first function for accommodating a surgical instrument or partthereof (ex: forceps) that makes it possible to exert an externalbending force on the frame to cause its bending and jaws opening asexplained above.

In this respect, the axial supporting members 24, 26 may each comprise afirst receiving portion 24 a, 26 a outwardly oriented relative to theframe (FIGS. 2 and 3), i.e. opposite the beams 18, 20.

Here the first receiving portion takes the shape of a longitudinal oraxial groove opening out to the outside of the frame and running alongthe length of the supporting members. The two grooves are opening out ontwo opposite directions respectively. Each groove has a concave shapewhich may be adapted to that of the instrument or part thereof in acomplementary manner. The opening of the groove may be centered on aplane XY in which the two beams 18, 20 extend. In alternateconfigurations, the groove may rather be oriented upwardly, i.e. with anopening that makes an angle with the above-mentioned plane.

Further, the axial supporting members 24, 26 may each comprise a secondreceiving portion 24 b, 26 b that is generally opposite the firstreceiving portion. Both second receiving portions are facing each otherand define there between a transverse space. They more particularlydefine there between together with the upper side or face of transversebeams 18, 20 (the upper side lies in an XY plane) a housing or slot thatis adapted to accommodate a cover member.

Second receiving portions 24 b, 26 b may take the shape of rails orgrooves that are inwardly oriented relative to the frame, i.e.substantially towards the beams. Second receiving portions 24 b, 26 bare more particularly located at a distance from the upper side of thebeams (FIG. 2). In the present embodiment, second receiving portions 24b, 26 b are each formed in the same portion of the supporting member asthat of the first receiving means. More particularly, each secondreceiving portion may be formed by one of the two edges that define anadjacent outwardly oriented groove (first receiving portion). This edgeis shaped so as to change its orientation towards the inner of the frameand make a bend. Thus the bend defines a concave portion that isinwardly oriented and may accommodate a cover member.

The cover implant body 10 also comprises a cover member 30 (FIGS. 4A-C)that is intended to be assembled with the frame 12. The invention mayalso concern cover implants with more than two parts, e.g. the frameand/or the cover member may be made of more than one piece.

The cover member 30 comprises two portions (see FIG. 4A which is a topor front view):

a mechanical portion 32, and

an opaque optical portion 34.

The two portions form together a single piece in the present embodiment.They may have each the same thickness along axis Z (FIG. 2). Here thecover member may take the form of a foil, e.g. a relatively thin foil.

The mechanical portion 32 is to be assembled with the frame 12 thanks tothe second receiving portions 24, 26 described above.

The mechanical portion 32 and the opaque optical portion 34 are alignedto each other along the longitudinal axis X. Both mechanical portion 32and opaque optical portion 34 extend in a plane XY (parallel to theplane of extension of the two beams 18, 20).

Here the cover member visible on FIG. 4A has a face (upper face) thathas two zones corresponding to portions 32 and 34 respectively. When thecover member is assembled with the frame, this upper face forms a firstface that is opposite the face of the frame that carries the attachmentmembers. The mechanical portion 32 may be transparent to light andmaintain the initial aspect of the iris (the corresponding first zone ofthe upper face of the cover member is therefore not opaque). Themechanical portion 32 may alternatively be pigmented or textured so asto produce a visual effect (ex: pigments as those of an iris). Thecorresponding first zone of the upper face of the cover member istherefore opaque.

When viewed from above (as in FIG. 4A), the mechanical portion 32 has asubstantially rectangular shape with two substantially parallellongitudinal edges 32 a, 32 b, a rear edge 32 c with a convex shape.

The opaque optical portion 34 axially extends mechanical portion 32 atits front zone by an appropriate shape that may vary according to theembodiments. The portion 34 has a function of being opaque, i.e. nontransparent to light so as to produce a stenopeic or pinhole effect.Here this is the second zone 34 a of the upper face of the cover memberthat is opaque. Generally, the portion 34 may be opaque across its wholethickness (FIGS. 4A and 4C) that is intended to be oriented in thedirection the eye is looking at when the cover implant 10 is installedon the iris of the eye. Thus the opaque optical portion 34 is configuredto receive incident light and stop corresponding rays. In a preferredembodiment, portion 34 is a black optical portion. In alternativeembodiments other opaque visual appearance for face 34 a such ascolored, pigmented visual appearance, may be envisaged.

Here the opaque optical portion 34 has two converging edges 34 b 34 cthat extend from longitudinal edges 32 a, 32 b respectively andterminate at an end edge 32 d that extends transversally and connectsboth inclined edges 34 b, 34 c.

Edges 34 b and 34 c have a geometry that adapts to the geometry of otheropaque optical portion edges of adjacent cover implants when all areinstalled on the iris of an eye around the pupil and the latter is inits most constricted position as will be seen subsequently. Here theinclination angle of the edges is the same for all the opaque opticalportion edges of the cover implants so that two adjacent convergingedges of two adjacent cover implants are in contact. Thus, no light willbe able to pass between two adjacent edges in this embodiment. FIG. 11Cillustrates this pupil position with all cover implants 10 in closerelationship to each other. To be noted that in other cover implantsconfigurations light may pass between adjacent cover implants withoutadversely affecting the stenopeic effect. This is the case in particularwhen the gap between adjacent cover implants represents a smallnegligible portion of the whole diaphragm (e.g. on the order of 3 or5%). End edge 34 d has here a concave shape in a top view that is ableto reproduce as much as possible an overall substantially circularoutline when all the cover implants are installed on the iris of an eyeand the latter is in the most constricted position of the pupil.

Put it another way, when all the cover implants are in a closerelationship (most constricted position of the pupil) adjacent to eachother, the opaque optical portions form, and act as, a whole diaphragmthat is as homogeneous as possible (continuity in the opacity).

Different other possible shapes of opaque optical portions will bedescribed later on.

As illustrated in FIG. 4A, opaque optical portion 34 is bounded by aline 34 e that is at the frontier with mechanical portion 32 andseparates both portions. Line 34 e has substantially the same curvatureas edge 34 d so as to define there between a portion of an annular shapeor annulus. All these opaque portions placed side by side in the mostconstricted position of the pupil form a continuous opaque annular orring shape (diaphragm of FIG. 11C).

As represented in FIG. 4A, the length or axial extension of opticalportion 34 is smaller than that of mechanical portion 32 and forinstance may be half the length of the latter. By way of example thetotal length of both portions is 2.22 mm.

The cover member is able to be elastically deformed, i.e. here bybending around its longitudinal axis (parallel to axis X). The bendingmovement takes place in the plane Y, Z.

In a general manner, the cover member 30 overall extends in a plane (XYplane). It is however elastically deformed as represented in FIGS. 4Band 4C in order to be assembled with the frame as will be seensubsequently. This is because the beams 18, 20 have raised lateralportions (see FIG. 2). Once the cover member has been elasticallydeformed by bending and assembled with the frame the cover member keepsinside a residual stress that makes it possible to be maintained inposition within the frame.

As represented in FIGS. 4B and 4C, the cover member 30, in its initialnon deformed position, has a substantially curved shape along itslongitudinal axis, e.g. as a tile.

Here cover member 30 is flexible and may be made, e.g. of silicon orhydrophilic acrylics or hydrophobic acrylic or elastomer.

FIGS. 6A-C illustrate the assembling process of the cover member 30 andframe 12.

In FIG. 6A, cover member 30 is held by a forceps in a slightly foldedconfiguration and moved towards the frame along longitudinal axis X withthe rear zone (edge 32 c) facing the frame. The frame is placed with itssecond receiving portions 24 b, 26 b oriented upward and attachmentmembers downward. To be noted that frame 12 has no front and rear parts(this however may be the case for other frame embodiments), which makesthe assembling process easier and faster.

Prior to any assembling operation the cover member 30 is bent asexplained above (this is done through using conventional forceps asrepresented in FIG. 6A) to take a curved shape which substantiallycorresponds to the inner frame outline defined by the upper face of theframe (upper face of beams 18, 20) and the raised lateral portions 24 b,26 b (ex: the flared inner shape of the lateral supporting members 24,26) of the frame. In a transverse cross section the inner frame outlinehas substantially a U shape and defines an open housing foraccommodating cover member 30.

The longitudinal edges 32 a and 32 b are engaged or inserted into secondreceiving portions 24 b, 26 b above cross beams 18, 20 and then arecaused to slide along these portions (ex: in the rails or grooves) asillustrated in FIG. 6B.

The cover member 30 is axially pushed until the opaque optical portion34 substantially reaches the free ends of second receiving portions 24 b26 b (FIG. 6c ). Appropriate local configuration(s) inside the secondreceiving portions may be provided to axially stop the sliding movementof cover member 30. By way of example, a lug or a slightly conical shapeformed by the whole set of the two second receiving portions may beused.

When the cover member has been assembled with the frame, these two partsare maintained together through friction and contact pressure.

Thus, opaque optical portion 34 axially extends (along axis X) beyondthe frame as a cantilevered beam. This holds true whatever the shape ofthe cover member, in particular the opaque optical portion. Thisarrangement makes it possible to attach the cover implant on the iris insuch a position that only the opaque optical portion extends beyond theiris edge or pupil margin (see e.g. the relative position between coverimplant 10 and iris edge E on FIG. 11A). To be noted that in FIG. 6C arear portion of the mechanical portion 32 also protrudes from the frameso as to serve as counterweight. In other embodiments the mechanicalportion may be flush with the frame.

Other embodiments not depicted here may cover an inverted configurationin which the frame is engaged inside the cover member. The cover membermay be designed so as to incorporate receiving portions foraccommodating the frame. For example, two receiving portions may extendrespectively from two substantially parallel edges of the cover member(as edges 32 a and 32 b), e.g. in a perpendicular direction to the covermember, and may cover the frame placed below on three or four sides as acap: the upper side and two downwardly extending lateral sides with apossible angled terminating portion extending under the frame so as toform a lower side. Assembling the cover member and the frame member maybe achieved by axially engaging the frame into the lower receivingportions of the cover member.

To be noted that the above-described assembling process equally appliesto any other cover implant embodiment with a frame, and possibly a covermember, having different configurations. For example, the frame may haveonly one transverse beam or more than two transverse beams as alreadyenvisaged above.

FIG. 7 illustrates a variant embodiment of a frame 40 with a singleattachment member. Here the attachment member is a clamping member 42that axially extends from one transverse beam 44 to the other 46.

Clamping member 42 has two axially elongated seizing portions or jawsthat behave as jaws 14 a, 14 b in FIGS. 5A-C. The jaws are each attachedto the lower face of the two beams. In this embodiment all the othercomponents of the frame are identical to those of the previous frames.To be noted that in other variant embodiments the attachment members maybe arranged differently relative to each other, e.g. not necessarilyalong the same axial direction of the frame (along axis X) but in alaterally offset position. The FIG. 7 embodiment and its variants mayapply to any other cover implant embodiments and variants as mentionedabove or below. FIGS. 8A and 8B illustrate an iris cover implant 50comprising a body that is made as a single piece for easiness ofmanufacture and implementation by a surgeon. The body comprises a covermember 52 and a frame 54 that are formed as a whole. Here the frame hasno second receiving portions. The cover member 52 has a mechanicalportion 52 a and an opaque optical portion 52 b that may have the samefeatures and advantages as for the embodiments and variants with atwo-part body. Frame 54 also comprises attachment members 56 with thesame features and functionalities as for the embodiments and variantswith a two-part body. The underside of the frame is recessed between thetwo attachment members so as to provide flexibility to the frame (notdepicted here). All that has been described above also applies to thepresent embodiment. In particular, the different attachment memberconfigurations mentioned above or below may equally apply to FIGS. 8A-Bembodiment. FIGS. 9A-C show various possible configurations of anattachment member fixed under a frame of an iris cover implant. FIGS.9A-C illustrate clamping members with two spaced apart clamping portionsor jaws of various sizes.

In FIG. 9A, the frame 60 is provided with a clamping member 62 that hastwo facing heads 62 a, 62 b linked to the underside of frame 60 throughrespective downwardly extending arms 62 c, 62 d.

In FIGS. 9B and 9C the respective frames 70 and 80 have clamping members72 and 82 with larger and larger heads and longer and longer arms.

Other possible configurations may be envisaged, e.g. with different headshapes, different number of seizing portions or jaws etc.

As for the previous embodiments the attachment members may be locatedunder the two spaced apart transverse beams in the central portionthereof or may be arranged at another location. As in FIG. 7 a singleattachment member may be provided under the frame. The frame may alsovary in shape. All that has been described above in relation with theattachment member(s), in particular with reference to FIGS. 5A-C, mayalso apply here.

To be noted that in FIGS. 9A-C the opposite first receiving portions ofeach frame have been schematically represented by a symmetrical grooverelative to the median plane X, Y of the transverse beams. In thepresent embodiments of FIGS. 9A-C the body of the cover implant (frameand cover member) may be made as a single piece and no second receivingportions are therefore necessary.

However, FIGS. 9A-C also apply to cover implants the body of which is intwo parts as in FIGS. 1 to 7.

The attachment members of FIGS. 9A-C may be used in any of the previousembodiments and variants.

FIGS. 10A-E illustrate various possible configurations of cover membersmounted to a frame 12 including the already described cover member ofFIG. 10A.

FIGS. 10B-E show different cover member configurations in which themechanical portion 32 remains the same as in FIG. 10A and the opaqueoptical portions differ from each other and from opaque optical portion34.

In FIG. 10B the cover member 30′ has a substantially T-shape with theopaque optical portion 34′ corresponding to the T crossbar.

The opaque optical portion 34′ has a substantially curved shape, e.g. abean shape, with a central curved zone 34′a and two side zones 34′b and34′c that laterally extend beyond portion 32 and frame 12 in a flaredmanner viewed from above. Central curved zone 34′a is axially alignedwith mechanical portion 32 when viewed from the above.

As for portion 34 in FIG. 10A, portion 34′ has rounded edges (no sharpangles). Central curved zone 34′a has the same kind of curvatures asportion 34 for the same reasons.

Side zones 34′b and 34′c are not lying in a plane as that of FIG. 10B.FIG. 10C represents an elevation view of the whole cover implant takenfrom the arrow F in FIG. 10B (from the end side of the diaphragm wherethe opaque optical portion 34′ is located). In this Figure the sidezones 34′b and 34′c are inclined relative to a XY plane P′ (herehorizontal in FIG. 10C) in which the transverse beams 18, 20substantially extend, at least in their main central portions. In thisslanted position the side zone 34′b forms an upper zone that extendsabove plane P′ and side zone 34′c forms a lower zone that extends belowplane P′.

This arrangement makes it possible to appropriately dispose adjacentopaque optical portions during the diaphragm closing (when the pupil isbeing constricted) so that they do not mechanically interfere withother. The adjacent opaque optical portions may thus partially overlapwhen seen from the above.

Such a configuration allows to provide an efficient homogeneous opaquediaphragm or cover with all the adjacent opaque optical portions of allthe cover implants.

In FIG. 10D the cover member 30″ has not a symmetrical shape when viewedfrom the above as for cover members 30 and 30′. In contrast, covermember 30″ has a substantially L shape with an opaque optical portion34″ extending sideways. Opaque optical portion 34″ has a central zone34″ a that is axially aligned with mechanical portion 32 when viewedfrom the above. Opaque optical portion 34″ has also a side zone 34″bthat extends laterally in a slanted and forward direction (viewed fromthe above) relative to the alignment axis of portions 34″a and 32.

Opaque optical portion 34″ has a curved end edge 34″c that issubstantially concave along its length so as to reproduce asubstantially circular outline when all the cover implants are adjacentto each other in the most closed configuration of the whole diaphragmimplant (pupil fully constricted).

More particularly, opaque optical portion 34″ has a double concavityinstead of a single one for opaque optical portions 34 and 34′.

FIG. 10E shows a rear view of the cover member 30″ (view along the arrowG of FIG. 10D) without its frame 12. As represented in this transverseview, opaque optical portion 34″ is not lying in a plane as opaqueoptical portion 34′ but makes an angle with the plane P″ (herehorizontal plane) in which mechanical portion substantially lies.

This arrangement makes it possible to appropriately dispose adjacentopaque optical portions during the diaphragm closing (when the pupil isbeing constricted) so that they do not mechanically interfere withother. The adjacent opaque optical portions may thus partially overlapwhen seen from the above.

Such a configuration allows to provide an efficient continuous opaquediaphragm or cover with all the adjacent opaque optical portions of allthe cover implants. All that has been described above in relation withFIGS. 1 to 9C (ex: attachment member(s), two-part or single part covermember) may also apply to the embodiments of FIGS. 10A-E.

FIGS. 11A-C show a plurality of iris cover implants 10 implanted (inparticular attached) on the anterior surface of a human iris I. When notimplanted on the iris, the plurality of cover implants 10 form asurgical kit that is ready for use by the surgeon.

In a variant the surgical kit may comprise separate cover members andseparate frames (when the cover implants are not in a single piece) thatneed to be assembled together prior to any iris implantation by thesurgeon.

FIGS. 11A-C show different positions of the pupil.

In the initial dilated position (fully open) of FIG. 11A the coverimplants 10 are radially arranged relative to the centre of centralaperture O1 with their longitudinal axis (X) radially oriented and faraway from each other.

The central aperture O1 bounded by the iris sphincter edge E is at itsmaximum diameter (ex: 7 mm).

The cover implants 10 have a rather small opaque optical portion 34 suchthat in this dilated position where they are far from each other theymay be considered as not affecting the vision.

In FIG. 11B the pupil is partially constricted and the central aperturehas reduced to O2 (the reduced diameter is e.g. of 4.5 mm).

The cover implants 10 are caused to be moved by the iris movement andget closer to the center of the aperture and from each other (dynamicimplant the movement of which is controlled by the natural movement ofthe iris). In FIG. 11C the pupil is fully constricted and the centralaperture has reduced to O3 (the reduced diameter is e.g. of 3 mm).

The cover implants 10 come into contact with each other two by two or invery close proximity so that the opaque optical portions 34 form alltogether a substantially continuous opaque diaphragm or zone (ex: here aband-shaped zone) around reduced aperture O3. This produces a pinhole orstenopeic effect which increases the depth of field.

Here the close contact or proximity between the adjacent cover implants10 is made possible thanks to the shapes of the opaque optical portions34 that are adjusted to be positioned side by side in a same plane.

FIGS. 12A-C show a plurality of the iris cover implants 30″ of FIGS.10D-E implanted (in particular attached) on the anterior surface of ahuman iris I as in FIGS. 11A-C and with the same pupil movements.

In contrast to cover implants 10, cover implants 30″ are not lying in aplanar configuration due to their upwardly inclined or raised side zones34″b (see FIG. 10E).

In the dilated position of FIG. 12A, the mechanical portions 32 of coverimplants 30″ are spaced apart from each other whereas the adjacentopaque optical portions 34″ are rather close to each other. However, itdoes not matter since the aperture O1 is large enough.

In FIG. 12B the cover implants 30″ already overlap each other due totheir laterally extending opaque optical portions 34″, in particulartheir raised side zones 34″b. The side zone 34″b of each opaque opticalportion 34″ partially overlaps central zone 34″a of the adjacent opaqueoptical portion 34″ in the left position. This arrangement creates asubstantially continuous opaque annular or ring shape diaphragm aroundaperture O2 (this therefore starts the pinhole effect process) whereasin corresponding FIG. 11b the cover implants 10 are farther from eachother (no pinhole effect has been created yet). In FIG. 12B, themechanical portions 32 of the cover implants 30″ are at a distance fromeach other as in FIG. 11B.

In FIG. 12C the cover implants 30″ get closer to each other as the pupilreduces to aperture O3. The cover implants 30″ come into contact witheach other two by two or in very close proximity by their mechanicalportions 32 (as in FIG. 11C). The side zones 34″b of the opaque opticalportions 34″ are no longer laid out along the annular or ring shape ofFIG. 12B. They are now angularly shifted towards the outside of apertureO3, i.e. oriented outwardly from the annular shape.

FIGS. 13A-D show different configurations of opaque optical portions inthe most constricted position of the pupil. The diameter of theconstricted pupil is denoted by D.

In these Figures the opaque optical portions may overlap (since theyhave not a planar configuration) two by two not necessarily in a regularmanner. These opaque optical portions have all end or terminating edgesthat are at least partially facing the central aperture O3 of the pupilwhen the corresponding cover implants are close to each other.

What matters is that the outline of the central aperture O3 bounded bythese end edges be located in an annular zone AZ centered on a diameteror circle D1 that corresponds to the targeted diameter for the diaphragmin the most constricted pupil position so as to obtain the desiredstenopeic effect. The zone Z is outwardly bounded by two circular linesC1 and C2 that represent tolerances margins with respect to the targetD1.

In FIG. 13A the opaque optical portions have a configuration with aconcave end edge 34 d as in FIG. 4A but the opaque optical portions areslanted relative to an XY planar configuration so as to be able tooverlap as illustrated in FIG. 13A. The opaque optical portions arearranged in such a way to form an outline S1 bounding aperture O3 thatis irregular in shape but contained within zone Z.

In FIG. 13B the opaque optical portions have a configuration with arectilinear end edge 34′d and are slanted relative to an XY planarconfiguration so as to be able to overlap as illustrated in FIG. 13B.The opaque optical portions are arranged in such a way to form anoutline S2 bounding aperture O3 that is here regular in shape (anhexahedron) and contained within zone Z.

In FIG. 13C the opaque optical portions have a configuration in whichthe end edge 34″d has an uneven relief and the opaque optical portionsare slanted relative to an XY planar configuration so as to be able tooverlap as illustrated in FIG. 13C. The opaque optical portions arearranged in such a way to form an outline S3 bounding aperture O3 thatis here irregular in shape and contained within zone Z.

In FIG. 13D the opaque optical portions have a configuration in whichthe end edge 34′″d has a concave shape and the opaque optical portionsare slanted relative to an XY planar configuration so as to be able tooverlap as illustrated in FIG. 13D. The configuration of the opaqueoptical portions is as that of FIGS. 10D and E with an inverted shape(the lateral extension is on the right of central zone 34″a). The opaqueoptical portions are arranged in such a way to form an outline S4bounding aperture O3 that is here irregular in shape and containedwithin zone Z. All that has been described with reference to FIGS.11A-13D may also apply to any other cover implant configurations asthose mentioned above in relation with FIGS. 1 to 10E.

FIGS. 14A-D illustrate the main steps of a possible surgical method forimplanting on the anterior surface of iris I a plurality of iris coverimplants as any of the above-mentioned cover implants, e.g. coverimplants 10.

In the present embodiment the cover implants may form part of a surgicalkit.

In a first step (FIG. 14A), the cornea Cr of the eye is incised e.g.using a conventional surgical instrument, e.g. a surgical blade 100.Alternatively a femtosecond laser may be used to make an incision Inc.The incision may be a limbal self-sealing clear corneal tunnel incisionor a self-sealing scleral tunnel incision. The width of the incision mayvary between 1 and 4 mm.

In a further step (FIG. 14B) another instrument 110 is used, e.g. adedicated folding forceps, to grasp a cover implant 10 and introduce itthrough the incision Inc.

The forceps include a pair of arms 112, 114 that flank the cover implant10 along its longitudinal edges (supporting members 24, 26). Inparticular, arms 112, 114 are engaged into the respective firstreceiving portions 24 a, 26 a (the latter have shapes that are adaptedto that of the arms, i.e. a semi-cylindrical shape to house acylindrical or substantially cylindrical shape) to carry the coverimplant 10.

Alternatively, the cover implant 10 may be loaded into a dedicatedcartridge injector and then inserted through the corneal or scleraltunnel incision into the anterior chamber of the eye.

When the cover implant 10 is above the iris (FIG. 14B), at the requiredposition the forceps may be tightened so that the arms 112, 114 exert aclamping effort on the first receiving portions 24 a, 26 a of the coverimplant as indicated by the facing arrows on enlarged FIG. 14C. Thisclamping effort causes the cover implant to elastically bend as alreadyexplained with reference to FIGS. 5A-C (the bending movement takes placeabout a longitudinal direction). The attachment members 14, 16 are thencaused to open above an iris radial ridge (natural fold of the irissurface) P to be clamped in a position adjacent to the pupil edge E.

Thus the cover implant 10 moves towards the radial ridge (ex: downwardmovement if the patient is in an horizontal position) until the latterlies between the two clamping portions or jaws. Once correctlypositioned on either part of the ridge P, the clamping effort can stopso that the two clamping portions or jaws can clamp the ridge asillustrated by FIG. 14D as a consequence of elastic return of the coverimplant frame. The cover implant is therefore released from theinstrument and positioned as illustrated in FIG. 11A with the frame 12and mechanical portion 32 above the iris and the cantilevered opaqueoptical portion 34 above the pupil aperture O1.

The same process is repeated (from FIG. 14B) as many times as the numberof cover implants 10 to be implanted.

To be noted that radial and longitudinal positioning of the coverimplant may be guided by means of a dedicated corneal marker impregnatedwith sterile biocompatible ink to indicate the central optical clearzone (minimum diaphragm diameter) and any adequate number of equallyspaced radii or by any other optical means including the projection of apattern of visible laser light through the cornea onto the iris surface.

More generally, the surgeon may use a positioning assist system,including inter alia an optical guide target (e.g. a laser with avisible wavelength) that will represents the optimal position of theimplants on the iris, through the cornea.

The method may be performed with the pupil in its more constrictedposition so as to optimize implants positioning in order to have in thisposition an artificial diaphragm with a minimum diameter and withrelative positioning of the implants that ensures no mechanicalblocking.

Generally speaking, the opaque optical portion (or at least the opaqueoptical face of the cover member) of the iris cover implant may bedesigned according to various geometrical shapes (see for example FIGS.10A-E, 13A-D and FIGS. 16-17) in order to optimize the opticalcontinuity of the dynamic diaphragm effect when pupil diameter changeswith light adaptation or accommodation. The shape of the opaque portion(or at least the opaque optical face of the cover member) may includeadditional oversized flange that may be tilted to create an overlappingeffect with adjacent cover implants.

FIGS. 15 to 18 illustrate other applications for a new iris coverimplant according to the invention.

FIG. 15 illustrates an embodiment of an iris cover implant 120 that isintended to partially cover the iris only (no optical diaphragm functionis present here).

Cover implant 120 comprises a cover member 122 corresponding to covermember 32 of FIG. 4A and a frame 124 corresponding to frame 12 of FIGS.1-3 and which is assembled with cover member 122, e.g. as previouslydescribed. Cover member 122 has an opaque face (upper face visible froma top view; the attachment members are located on an opposite face ofthe frame) and may be entirely opaque. Cover implant 120 mayalternatively be made in a single piece.

The axial extension (along axis X) of cover member 122, and possiblyframe 124, may be lengthened so as to cover a greater area of the irisanterior surface.

FIGS. 16A-D illustrate an embodiment of an assembly of several coverimplants 132, 134 (here two facing segments are represented, e.g. havingeach a U shape, but more than two segments may be used in an alternativeembodiment) forming a single intraocular implant which here acts both asa diaphragm and a partial artificial iris (iris cover). The partial iriscover may cover/overlap local iris deformities etc.

The two cover implants 132, 134 are assembled with each other through asliding arrangement. However, other alternative assembling arrangementsmay be envisaged.

Each cover implant comprises a body having a frame 136 with attachmentmembers 138 (FIG. 16D) as frame 12 in FIGS. 1-3 and a cover member 140,142. Cover member 140 has an opaque face (upper face visible from a topview; the attachment members are located on an opposite face of theframe) and may be wholly opaque.

Each cover member 140, 142 has two portions:

a main identical portion 144 as mechanical portion 32 in FIG. 4A;

a secondary portion that has two laterally extending arms 148, 150 and152, 154 both connected to main portion 144.

The two arms of the two cover members are in register with each other.

One of the two arms lies substantially in a plane as that of FIGS. 16A-C(planar configuration) whereas the other arm is in a raised positionrelative to the first arm and at an angle with the latter.

FIG. 16D shows the inclined raised arms 148, 154 of the two facing covermembers that are mechanically engaged into each other to form anassembly.

This arrangement makes it possible for each raised arm of a cover memberto overlap, to a small or greater extent, the corresponding planar armof the other cover member (see FIGS. 16A-C).

The raised arms are each provided with a protruding member, e.g. a lug,a rib etc., 148 a, 154 a (FIG. 16D) and the planar arms are eachprovided with a longitudinal slot 150 a, 152 a (FIG. 16A) in which theprotruding member is able to axially slide (along axis X) so that thetwo cover members can move relative to each other as in FIGS. 16A-C.Here the protruding members are downwardly extending from the lower faceof the arms.

The two arms of each cover member comprise each a first zone Z1corresponding to an opaque optical zone that is intended to play therole of a diaphragm (this is an optical portion with an optical face).

The two arms of each cover member also comprise each a second zone Z2and Z2′ corresponding to an opaque non optical zone. Zone Z2, Z2′ hastwo spaced apart portions that flank the first central zone Z1.

The above described sliding arrangement is carried by second zone Z2,Z2′, in particular, by the two spaced apart portions that flank thefirst central zone Z1.

In FIG. 16A, a circle C3 identifies the natural dilated pupil with acentral aperture O10. In this position the two zones Z1 extend aboveaperture O10 and zones Z2 and Z2′ partially extend above aperture O10.

In FIGS. 16B and 16C, the circles C4, C5 identify respectively more andmore constricted pupil positions. In these positions the two zones Z1extend above reduced apertures O11 and O12 respectively whereas zones Z2and Z2′ do no longer overlap these apertures. The two zones Z1 act as adiaphragm, in particular in the fully constricted position of FIG. 16C.The zones Z2 and Z2′ act as an artificial iris and cover a part of thenatural iris.

In the present embodiment the main portions 144 and the zones Z2 and Z2′have each a transparent face or an opaque one (pigmented, texturedand/or colored or not) so as to cover the iris either for locallymasking a deformity, etc. and/or for aesthetic reasons (color changeetc.).

The zones Z1 have both an opaque optical face (the whole zones in theirentirety may be opaque), e.g. a black face to play the role of adiaphragm when moved close to each other as in FIG. 16C.

FIG. 17 illustrates the assembly 130 of FIGS. 16A-D attached to theanterior surface of iris I.

Other configurations may be envisaged depending on the anatomy of thepatient's eye and his/her optical disorders. In particular, differentshapes of iris cover implants, arms etc. may be envisaged to more orless cover the natural iris.

FIG. 18 illustrates another assembly 160 of several iris cover implantswith no optical diaphragm function. Assembly 160 represents anartificial iris implant that covers at least partially the natural iris.Here the cover implants 162, 164 have a similar U shape as that ofassembly 130 but, alternatively, may take any other shape. The two armsof each cover implant have a greater cover area than that of assembly130 above the iris so as to overlap the latter to a greater extent. Theoptical zone of the arms extending beyond the iris edge has been removedhere. The two arms of each cover implant extend laterally with respectto the main portion 144 of the cover member and rearwardly relative tomain portion 144 so as to flank the latter on either side. The shape ofthe arms may vary according to the zone of the iris to be covered as forassembly 130 and may cover the whole iris (a few rules have to be takeninto account for placing such an implant as will be seen subsequently)or not.

The features and advantages of assembly also apply here to assembly 160.

FIGS. 19A-C show the implantation of cover implants on the anteriorsurface of an iris I. this may apply to any of the above-mentioned coverimplants.

In FIG. 19A, a set of several cover implants 170 are represented mountedonto the iris, around the pupil. FIG. 19A shows an upper and a lowerview: in the upper view the iris is in a dilated position whereas it isin a fully constricted position in the lower view. The whole externaldiameter of the iris (at its base) is referred to as D and C representsthe radial displacement or travel of the iris between the two extremepositions. For example, the pupil diameter may be equal to 7 mm in thedilated position and to 3 mm in the fully constricted position, whichleads to a 2 mm stroke for C.

FIG. 19B represents a shape of a truncated cone with an angle α at itsbasis, a base with a width L that is less or equal than D-C and a heighth.

This volume represents a typical volume V in which the cover implant(s)according to the invention may be installed, being understood that asecurity margin has to be taken so as to avoid placing an implant whichwould be in contact or too close to the iridocorneal angle (angle θ inFIG. 19C).

FIG. 19C illustrates the space that is authorized for installing animplant on the iris (the iris is not represented here for the sake ofsimplicity) given the size and shape of the cornea Cr.

The volume V has been represented in an offset position (this does notcorrespond to any actual design) to highlight the width C that is notauthorized for implant installation.

Generally speaking, the angle a of the allowed volume is less than theangle θ, for instance less than 60% of this angle so as to avoid anycontact between the implant(s) and the cornea Cr.

The length or width L is also preferable less than D-C for the samereasons.

The height h is less than the maximum axial distance A of the anteriorchamber and for instance less than 60% of this distance for the samereasons as above.

Put it another way, the constraints that have to be taken into accountbefore placing a cover implant on an iris depend on the actual diameterof the iris, the actual travel of the iris during its two extremepositions and the height of the cornea.

By way of example, for an average implant (i.e. an implant that is basedon an average of biological data measurements obtained on a plurality ofpatients) its length or width L and height should not go beyond 7.5 mmand 1.5 mm for space physiological reasons. Anyway, the size of theimplant is to be made as small as possible.

1. An iris cover implant intended to cover at least partially the irisof an eye, the cover implant comprising a body having a first face thatis an opaque face and, on an opposite second face, at least oneattachment member that extends outwardly from the body and is fixedthereto, the at least one attachment member comprising at least twoclamping portions that are able to attach the body to an iris of an eyeby clamping.
 2. The cover implant according to claim 1, wherein theopaque face extends at least in a plane that is substantiallyperpendicular to the direction of extension of the at least oneattachment member relative to the second face of the body.
 3. The coverimplant according to claim 1, wherein the at least two portions are ableto move away from each other under the action of an external force in aplane containing the direction of extension of the at least oneattachment member, the body being able to elastically bend within theplane when submitted to an external force so as to cause said at leasttwo portions to move away from each other from an initial position, saidat least two portions being able to return to their initial position inthe absence of any external force.
 4. The cover implant according toclaim 3, wherein the body has at least two receiving portions that areeach adapted to receive an instrument or a portion of an instrument forelastically bending the body.
 5. The cover implant according to claim 1,wherein the at least one attachment member is integral with the body. 6.The cover implant according to claim 1, wherein the at least twoattachment members are spaced apart from each other along a firstdirection that is substantially perpendicular to the direction ofextension of the at least one attachment member relative to the secondface of the body, the body having a thickness along the direction ofextension of the at least one attachment member relative to the secondface of the body, the thickness of the body being reduced in a zone ofthe body that is located between the two zones where the at least twoattachment members are disposed.
 7. The cover implant according to claim1, wherein the body comprises a frame provided with the at least oneattachment member and a cover member assembled with the frame, the covermember including the opaque face.
 8. The cover implant according toclaim 7, wherein the frame and the cover member are mechanically engagedwith each other.
 9. The cover implant according to claim 8, wherein theframe has second receiving portions that are each adapted to receive thecover member.
 10. The cover implant according to claim 6, wherein theframe comprises two parallel spaced apart beams with two attachmentmembers located on the two beams respectively.
 11. The cover implantaccording to claim 7, wherein the cover member also includes amechanical portion that is assembled with the frame.
 12. The coverimplant according to claim to 7, wherein the cover member and the frameare each able to be elastically deformed.
 13. The cover implantaccording to claim 1, wherein the body comprises a frame provided withthe at least one attachment member and a cover member including theopaque face, the frame and the cover member being made of a singlepiece.
 14. The cover implant according to claim 1, wherein the opaqueface has at least one zone that is an opaque optical face.
 15. The coverimplant according to claim 7, wherein the opaque optical face belongs toan optical portion that extends beyond the frame.
 16. A surgical kitcomprising: a plurality of cover implants as in claim 1, the pluralityof cover implants forming a multi-component iris cover implant acting asa diaphragm when attached to an iris of an eye.
 17. A surgical kitcomprising: a plurality of cover implants as in claim 1, the pluralityof cover implants forming a multi-component iris cover implant acting asa partial or total artificial iris when attached to an iris of an eye.18. An assembly of several cover implants as in claim 1, the pluralityof cover implants forming a single iris cover implant acting as adiaphragm when attached to an iris of an eye.
 19. An assembly of severalcover implants as in claim 1, the plurality of cover implants forming asingle iris cover implant acting as a partial or total artificial iriswhen attached to an iris of an eye.